ARM Sheds New Light on High-End Cortex-A72 CPU

At yesterday’s annual Tech Day event, ARM shared more details about their upcoming Cortex-A72 architecture. Set to replace the current A57 performance chips, this new replacement is set to be faster, more efficient, and doing it all with a smaller die. While the A72 is the high-performance successor, it’s still largely based on the previous A57 design.

Starting off, ARM is making big claims against the previous generation A15 cores. For the same workload in a smartphone, ARM is expecting to reduce power consumption by 75% or keep the same power levels and increase performance by 3.5 times. Of course, part of the gains are due to process improvements but about 66% of those gains come from the architecture. Of course, the A72 is also a 64bit design. Most of the changes are deep down in the chip, ARM having gone through and optimized everything. Branch prediction is improved by about 20% over the A57 and pretty every compute unit got latency reductions in the 25 to 50% range. Combined, these changes should yield about a 16 to 30% IPC increase at the same power as the A57. This lead is set to grow since the reduced die size also helps the A72 achieve higher clock speeds than before.

While beating the previous generation ARM processors is expected, the bigger question is how these improvements will fare against Intel’s Broadwell and Cherry Trial chips. Pitting a 2Ghz Core-M5Y10C against a 2.5Ghz Cortex A72, the ARM chip manages to hold it’s own. Once power is limited though, the A72 manages to pull ahead as Core-M starts throttling. Of course, we don’t know the specifics of the test, but its good food for thought nonetheless. If ARM is able to keep up their pace, Intel will soon be seriously challenged, and not just in the mobile space.

For now though, consumers will have to wait for the A72. It will be up to ARM partners like MediaTek, Qualcomm and Samsung to implement their own A72 designs. While ARM has done much to improve over the A57, it remains up to their partners to make sure it all works out, an issue highlighted by the Snapdragon 810. Earliest chips are set to ship later this year, pointing to release in mobile devices for 2016. Who knows, maybe the A72 might make it in time for the next Nexus phone?